[arjunb]

A more complex but potentially fairer variation of this idea is to create an ecosystem where each sender posts a bond when delivering a message to an unknown recipient. If the recipient finds the message abusive/spammy, they could flag it as such and claim the bond, otherwise the message is received without a cost to the sender.

[niggler]

Facebook is looking to make money off of this. Your proposal results in 0 profit for facebook.

EDIT: to the downvoter -- explain how the $1 proposal doesn't have a profit motive.

[ximeng]

Didn't downvote, but they could just as well take 20% of the bond as a fee.

Facebook could also charge $1 and give 50c to the user for receiving the message rather than keeping the whole dollar.

[niggler]

"otherwise the message is received without a cost to the sender"

Sure FB could take a cut of each message fee but that wasn't the OP proposal

[ximeng]

No, but it is compatible with the motivation behind it.